Apple refreshed the 27-inch iMac lineup on August 4, 2020, introducing 10th-generation Intel processors, more RAM, more SSD storage, faster AMD GPUs, and True Tone support for the display.
The 27-inch iMac update was an update to the internals and the display only and there were no major design changes to the body of the machine. The 21.5-inch iMac received no refresh, though it does now ship with an SSD by default rather than a Fusion Drive. It otherwise continues to have the same hardware introduced in March 2019.
Both the 21.5 and 27-inch 4K and 5K iMacs continue to use the same “ultra-thin” slim-bodied design first introduced in 2012, though a new model with an updated design and Apple Silicon chip is said to be coming in 2020 or 2021.
Apple updated the display of the 27-inch model, introducing support for True Tone functionality for the first time. True Tone adjusts the white balance of the display to the lighting of the room that you’re in for a more natural viewing experience.
There’s also a new nano-texture glass option that was first brought to the Pro Display XDR, and which is available for the iMac for an extra $500. Nano-texture glass offers better viewing under bright lighting conditions and it adds a matte finish.
Other than True Tone and nano-texture glass, the display of the 27-inch iMac is otherwise unchanged. Both iMac models feature 500 nits brightness, 1 billion colors, and support for P3 wide color.
Inside, the 27-inch iMac is equipped with Intel’s 10th-generation chips with up to 10 cores at the high end. Turbo Boost speeds can reach up to 5.0GHz for 65 percent faster CPU performance.
Apple added Radeon Pro 5000 graphics to the new 27.5-inch iMac, which is up to 55 percent faster than the GPUs in prior-generation 27-inch iMac models. The high-end Radeon Pro 5000 option supports 16GB of video memory for the first time, double the memory capacity.